Method of and apparatus for looping tape around tampons

ABSTRACT

Method of and apparatus for looping a double-thickness withdrawal tape around an absorbent cotton fleece used particularly for the manufacture of tampons for feminine hygiene.

United States Patent Simon 1 1 June 4, 1974 [5 METHOD OF AND APPARATUS FOR 2.934.068 4/1960 Graham ct a1. 19/1445 x LOOPlNG TAPE AROUND TAMPONS 3,063,453 11/1962 Brecht 19/1445 X y 3.318.623 5/1967 Burroso 289/15 [75] Inventor: tefan im n, M dlmg. ustr a 3,348,866 10/1967 Eu. 289/2 x Assignee: Dr Carl Hahn GmbH, Dusseldorf, 3,473,292 10/1969 Gaudhtz 289/18 X Germany Filed! 21, 1972 Primary ExaminerL0uis K. Rimrodt [21 APPL 236,626 Armrney, Agent, or FirmJas0n Lipow [30] Foreign Application Priority Data Mar. 21. Germany 2i [52] US. Cl 289/].5, 19/1445, 289/18 [511 Int. Cl B65h 69/04 Method of and apparatus for loopmg a double- 5 Field f Search 2 9/15 2 1 19/1445 thickness withdrawal tape around an absorbent cotton fleece used particularly for the manufacture of tam- 5 References Ci pens for feminine hygiene.

14 Claims, 31 Drawing Figures ATENTEU N 41914 3814.469

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sum '11 [1F 11 METHOD OF AND APPARATUS FOR LOOPING TAPE AROUND TAMPONS' The invention relates to a method of and an apparatus for looping a double-thickness withdrawal tape around an absorbent cotton'fleece used in particular for manufacturing tampons for feminine hygiene, for passing the open ends through the closed end and for drawing the withdrawal tape taut until the absorbent cotton fleece is closely encircled by the loop formed, the path of rotation of a continuously rotating threadpuller enclosing the absorbent cotton fleece as well as a withdrawal tape receiver device for axially guiding the absorbent cotton fleece transversely to the plane of rotation of the thread-puller, and a loop throw-off device, the thread-puller being provided with a control device which is adjustable by control cams against the action of restoring springs.

Such loops are, in cadence with the manufacturing process, to be so applied at definite fixed intervals onto a fleece strip which is to be fed continuously or intermittently to the manufacturing apparatus that the loops are correctly positioned when they reach the next processing station, e.g., a winding station, where the portions of fleece are wound in the direction of their longitudinal axis and are then pressed to the final tampon size in a tampon press.

Known apparatuses for looping produce only relatively short loops by the sewing process and, by reason of the numerous movements in the sequence, are not in a position to deliver the desired large numbers of loops per minute.

Therefore, the object of the invention is to provide an apparatus which is capable of supplying a large quantity per minute particularly of the very long loops, by virtue of its favourable kinematic design, while being of simple and reliable construction.

The invention resolves this problem in that the withdrawal tape is gripped behind its leading end which is clamped firmly in a clamping and cutting device disposed to rotate within the path of rotation of the thread-puller, by an entraining means on the threadpuller, and is partly laid around the receiver device the double withdrawal tape, in the region of the dead centre of the thread-puller which is opposite the clamping and cutting device, being gripped by a thread guide movable approximately in the plane of rotation of the thread-puller, after which it is cut through by the clamping and cutting device and released, while at the same time the following end of the withdrawal tape is clamped fast, whereupon the portion of withdrawal tape extending from the receiver device to the thread guide is diverted by the thread guide into a second outer plane in which it is gripped by a hook which is adapted to be pressed out of the entraining means of the thread-puller, while an ejector which can be pressed out of the thread-puller throws off the loop which is passed around the entraining means, over the two ends of withdrawal tape which are gripped by the hook, so forming a loop which, by means of the threadpuller, is drawn tight around the receiver device, the ends of the withdrawal tape gradually being released, after which the ejector device which encloses the receiver device pushes the loop formed onto the absorbent cotton fleece emerging from the receiver device.

Whichever hammer of the clamping and cutting device is not applied, so allowing passage of the withdrawal tape can, in the dead-centre position of the thread-puller which is directed away therefrom, be placed on the clamping sleeve for tying-off a fixed loop length, the withdrawal tape engaging with temporary tension into an upper brake clamp on the end of a shorter lever arm of a thread guide lever and into the thread guide, while in the subsequent relieving phase, the other hammer which was originally clamping the thread end cuts off the withdrawal tape connected to the supply spool and at the same time releases the end of the withdrawal tape clamped by this hammer.

Advantageously, cam-controlled operation of the ejector mushroom is envisaged once the hook, with the two ends of the withdrawal tape, has been retracted into the entraining means, grooves in the entraining means permitting a limited movement of the withdrawal tape in the longitudinal axis thereof, to allow the loop to fit snugly on the mouthpiece of the receiver .device before the free ends of the withdrawal tape leave the thread-puller.

A preferred apparatus for carrying out the aforementioned method is provided with an endless flexible member movable continuously in a vertical plane, on which a thread-puller is secured, the endless flexible member enclosing a loop ejector device and a withdrawal tape receiver device which guides the absorbent cotton fleece axially and transversely to the plane of rotation of the thread-puller, the thread-puller being provided with a control device which is adjustable by control cams against the action of restoring springs. This arrangement is characterised in that a clamping and cutting device consists of two hammers which are camoperated for axial/displacement within a rotatable clamping sleeve, and against the end face thereof, alternately clamping a thread, the hammers being however coupled to the clamping sleeve located coaxially of the axis of the reversing pulley for the endless flexible element for the thread-puller, in the direction of rotation, and in each case equipped with co-operating cutters, while inside the cylindrical entraining means of the thread-puller, the said mean being widened conically outwards forming a guide groove for the withdrawal tape, a cam-operated hook pin is mounted and is held by a thrust spring in an inoperative position, the said pin cooperating with a control cam, a cam-operated ejector mushroom located parallel with and at a distance from the hook pin, and in that the pivot point of a thread guide lever which is pivotable upwards'and downwards in the vertical plane of rotation of the thread-puller, between the withdrawal tape receiver device and the clamping and cutting device, is located at the height and in the vicinity of the latter, the free end of the long lever arm of the thread guide lever which is remote from the clamping and cutting device being a thread guide, one brake clamp being attached to each of the ends of two further substantially shorter arms of the thread guide lever, the receiver device for the withdrawal tape consisting of an intake channel for the absorbent cotton strip which is held in a mouthpiece which projects beyond the plane of movement of the withdrawal tape.

The thread guide itself may be expediently composed of a thread guide pin having an obliquely downwardly directed member which projects beyond the periphery thereof, a thread guide hook on the underside extending at an acute angle to the pin axis towards the side which is towards the centre of gravity of the threearmed lever, its front end being bent upwards approximately as far as the longitudinal centre of the thread guide nose, forming a fine gap and a thread chamber.

The brake clamps on the two short lever arms of the thread guide lever can in each case consist of a pin which is widened out at its outer end to form a plate which, on its rear face which is towards the lever arm, is provided with a thread guide chamber which extends in such a way that, according to the different angular positions, so the withdrawaltape finds a free space during the gripping action, the cross-section of the thread guide chamber being smaller than that of the double withdrawal tape, a plate disc displaceable on the pin bearing on the back of the plate under the pressure of a spring which encloses the pin, its other end being braced on the lever arm of the thread guide lever.

The drive for the three-armed brake guide lever may be so constructed that the disc mounted on an intermediate shaft has an eccentric stud projecting on the end face and engaging into the bore of a coupling pin, into the other bore of which a pin-member mounted eccentrically on the axis of the three-armed thread guide lever engages. So that upon a rotation of the intermediate shaft, the thread guide lever can be caused to perform an upwardly and downwardly directed pivoting movement via the pin-member.

Expediently, angular, cutters associated with each hammer form an acute angle with a counter-cutter mounted on the adjacent hammer, the angular cutters on each of the two hammers being held by means of springs against the cutting surfaces of the other cutter on the other hammer and being maintained nonrotatably by means of a guide pin.

An expedient further development of the threadpuller can reside in that the cylindrical entraining means projecting from the thread-puller is widened conically outwardly, forming a guide groove for the withdrawal tape, the outside of the hook-pin which is mounted in an inoperative position in the entraining means, by means of a thrust spring, being approximately flush with the outer face of the entraining means, while the rearward end of the stud on the hookpin co-operates with a control cam. At the same time, two small grooves in theentraining means can flank both sidesv of the hook, the grooves extending .from both sides and terminating in the free cross-section of the hook which is directed in the direction of rotation of the thread-puller. The plate-shaped ejector expediently engages into a recess in the annular shoulder and entraining means which, breaking through the guide groove for the withdrawal tape, extends in the entraining means to a location close to the hook-pin, the outer surface of the ejector mushroom, in the inoperative position thereof, being located-approximately in the plane formed by the line of the base of the guide groove. In a further development of the thread-puller, the mushroom is screwed into a guide sleeve, on the rear annular shoulder of which one end of a thrust spring is braced, its other end bearing on an inner annular shoulder in the thread-puller, a pin at the rear of the guide sleeve co-operating with a fixed control cam.

It is a good idea for the thread-puller housing to be constructed as a component part of the endless flexible member.

Expediently, the inlet passage of the receiver device corresponds in cross-section to the nominal width of the fleece, the mouthpiece of the inlet passage consisting of a very thin-walled steel nozzle, through which the fleece can be pulled in a somewhat smaller width .than in the inlet passage. An annular pusher which is axially displaceable on the fixed mouthpiece is adapted for displacement slightly beyond the mouthpiece.

A both simple and functionally reliable construction of thread-puller can be achieved if the cylindrical entraining means which projects from the thread-puller is widened conically outwardly to form a guide groove, a cam-operated hook-pin being mounted in the entraining means in an inoperative position by means of a thrust spring, in which p'osition the outside of the hook is approximately flush with the outside face of the entraining means, while the rearward end of the stud of the hook-pin co-operates with a control cam.

In order on the one hand to achieve a snug fitment of the loop on the receiver device and on the other however to ensure a secure guiding of the free ends of the loop during the time they are being gradually released by the thread-puller, a further feature is directed at the provision of two small grooves in the entraining means flanking the hook on both sides and extending from both sides in the free-cross section of the hook which is directed in the direction of rotation of the thread-puller. I I

A reliable ejection of the closed looped end over the free thread ends of the withdrawal tape which are held by the hook pin drawn into the entraining means can be achieved by a plate-shaped ejector engaging in a recess of the annular shoulder and entraining means which, breaking through the guide groove for the withdrawal tape, extends in the entraining means as far as a location close to the hook pin, the outer surface of the ejector mushroom, in the inoperative position thereof, being located approximately in the plane formed by the line of the base of the guide groove.

An expedient structural embodiment of ejector mushroom can be characterised in that the mushroom is screwed into a guide sleeve, on the rear annular shoulder of which is braced one end of a thrust spring, the other end of which bears on an inner annular shoulder in the thread puller, a pin on the rear-of the guide sleeve co-operating with a fixed control cam.

Thecam-controlled operation of the ejector mushroom is expediently envisaged once the hook, with the two ends of the withdrawal tape, has been retracted into the entraining means, the grooves in the latter permitting of limited movement of the withdrawal tape in its longitudinal axis to allow the loop to fit snugly on the mouthpiece of the receiver device before the free ends of the withdrawal tape leave the thread-puller.

It is a good idea for the thread-puller housing to be constructed as a link of an endless chain.

The receiver device for the loop of the withdrawal tape is expediently composed of an inlet passage for the fleece strip, the cross-section of which corresponds to the nominal width of the fleece and which terminates in a mouthpiece consisting of a very thin-walled steel nozzle which projects beyond the plane of movement of the withdrawal tape and through which the fleece strip can be pulled with a somewhat smaller width than in the inlet passage.

It is expedient for the loop to be pushed off onto the fleece by an annular pusher which is axially displaceable on the fixed mouthpiece, the pusher being adapted for displacement slightly beyond the mouthpiece.-

The invention is illustrated diagrammatically and by way of example in the attached drawings, in which:

FIGS. la, lb and It: show different phases of loop formation;

FIG. 2 is a view of the apparatus;

FIG. 3 is a section along the line Ill-Ill in FIG. 2;

FIGS. 4a, 4b, 4c, 4d, 42, 4f, 4g and 411 show various successive operating conditions of the apparatus during loop formation;

FIG. 5 is a view of a thread-puller;

FIG. 6 is a side view of the thread-puller in FIG. 5;

FIG. 7 is a section taken along the line Vll-Vll in FIG. 6;

FIG. 8 is a section taken along the line VIIIVIII in FIG. 6;

FIG. 9 shows the thread puller according to FIG. 6 in a lateral view and with the hook pin pushed out;

FIG. 10 is a side view of the thread-puller shown in FIG. 6, with the ejector mushroom pushed out;

. FIG. 11 is a view of the thread guide;

FIG. 12 shows the thread guide in FIG. 11, in plan view;

FIG. 13 is a section along the line XIII-XIII in FIG. 1 1;

FIG. 14 is a plan view of FIG. 11 from below;

FIG. 15 is a plan view of a brake clamp shown on an enlarged scale;

FIG. 16 is a section along the line XVIXVI in FIG. 15;

FIG. 17 is a section along the line XVII-XVII in FIG. 16;

FIG. 18 is a clamping and cutting device, in side elevation;

FIG. 19 is a section taken along the line XlX-XIX in FIG. 18;

FIG. 20 is a section taken along the line XX-XX in FIG. 19;

FIG. 21' shows the clamping and cutting device according to FIG. 18, comprising two hammers, with one hammer lifted-off a clamping sleeve, after completion of the cutting process and FIG. 22 shows the clamping and cutting device, according to FIG. 21, in the opposite operating condition compared with that shown in FIG. 21, with the hammer released and the cutting device open.

A withdrawal tape 40 which may consist for example of a cord or twine is looped as shown in FIGS. la, lb and 1c in a double thickness around an absorbent cotton fleece 36, its open ends 37 being threaded through its closed end, a loop 38 and being drawn taut until the resultant loop fits snugly around a mouthpiece enclosing the absorbent cotton fleece, without the elastic material thereof being however deformed, for example by being drawn in too tightly.

It is intended now first to describe the looping and looping-through process with reference to FIGS. 4a to 4h. The loop-forming cycle commences with the withdrawal tape 40 deposited in a clamping and cutting device A being gripped by a conical entraining means 44 of a thread-puller 12 (FIG. 4a). (In the drawings, the semi-circle which is shaded signifies the clamped position of the withdrawal tape).

The continuously counter-clockwise rotating threadpuller 12 transports the withdrawal tape into the lefthand dead-centre position of a chain guide 10 which is opposite the clamping and cutting device A. During this pulling-up of the withdrawal tape, a three-armed thread guide lever 29 operated in cadence with the apparatus by a crank drive 26, 27, 28 (FIG. 3) starts to pivot downwards from its top dead-centre position (FIG. 4b). When this happens, an upper brake clamp 31a of the three-armed thread guide lever grips the double withdrawal tape from below, while at the same time the withdrawal tape is controlled from above by a thread guide 30 mounted on the three-armed thread guide lever. The object of this thread guide is, on the one hand. in order to form the cross-over position of the withdrawal tape, to divert it out of a normal perpendicular thread plate 41 into a farther forward thread plane 42 (FIG. 3), and furthermore to guide the withdrawal tape in such a way that its crossed-over portion is gripped by a hook 45 of the thread-puller and is held under tension by reason of the fact that it has been diverted in the thread guide.

After the left-hand dead-centre position has been reached on the thread guide .10 (FIG. 40), the pullingup of the withdrawal tape is completed. The loop length is complete and the cutting phase is initiated.

A hitherto lifted second hammer 14 in the clamping and cutting device which, in its released position, allowed the withdrawal tape to be pulled up, now, controlled by a cam 17', is applied to a clamping sleeve 13, whereby a fixed loop length is tied off. Briefly, the continouously continued movement of the thread guide lever 29 leads to a slight buildup of tension in the withdrawal tape which overcomes the engaging resistance of the brake clamp 31a on the one hand and that of the thread guide 30 on the other (FIG. 40). This tension build-up is however immediately in the next phase of movement of the thread-puller l2, dissipated by a shortening of the distance between the thread-puller and the mouthpiece 25 of the receiver device B for the withdrawal tape (FIG. 4d). In the tension-reducing phase, then, by lifting or upwards control of the hammer 14a which has originally held the thread end clamped as shown in FIG. 4a, the withdrawal tape which is still attached to the reel is cut off by the cutter 34 located on this hammer, through the cam 17. At the same time, however, this lifting releases the ends of the withdrawal tape which is clamped by this hammer so that the double withdrawal tape is now firmly positioned, i.e., separated from the bank and ready for the looping-through operation (FIG. 4d).

The change-over of withdrawal tape is not completed, the end of the withdrawal tape leading to the reel is in the counter-hammer 14a and ready for a new loop-forming and looping-through process (FIG. 4a).

The further phase pattern of looping-through is completed now via the thread-puller l2 and thread guide 30 on the thread guide arm 29. In the phase shown in FIG. 4e, a hook 45 in the thread-puller 12 is lifted by a fixed control cam 35 (FIG. 2) and, during further movement of the thread-puller, engages the withdrawal tape (FIG. 4]) which is crossed from the mouthpiece to the valve and pulls it, still controlled by the cam 35, into the interior of the entraining means 44.

Grooves or recesses 44a in the entraining means allow the withdrawal tape movement, this movement being it is true restricted by the sharp deflection but being otherwise free, in the longitudinal axis, so that a build-up of tension in the now further reducing mouthpiece/thread-puller system is avoided.

Afterclosure of the hook 45, an ejector mushroom 47 controlled by a further fixed control cam 35a (FIG.

2) pushes the loop located on the entraining means axially off this latter (FIG. 4g). I

Loop formation is now in the finalphase which relates to the drawing taut of the loop through the mouth-' piece and around the absorbentcotton fleece, without any constriction of this latter.

By virtue of the restriction of the withdrawal tape in the entraining means 44, during the cycle of movement of the thread-puller puller in the drawings FIGS. 4g to 4h, the loop 38 fits entirely snugly to the mouthpiece 25 before the ends 37 leave the thread-puller (FIG. 4h). As -a result of the aforementioned restriction, this process takes place with tension in the withdrawal tape. Therefore, by utilising this tension, the withdrawal tape can be deposited in a brake clamp 31b which is approximately opposite the brake clamp 31a in order on the one hand to prevent any whip effect in the free end and on the other to allow the loop formed to be monitore in known manner.

The mouthpiece 25 is a very thin-walled steel nozzle through which the absorbent cotton fleece is pulled in a width somewhat smallerthan in the inlet passage 24 which corresponds to the nominal width of the absorbent cotton fleece. v

The loop can now bepassed around the fixed mouthpiece 25 independently of the movement of the absorbent cotton fleece and a pusher 23 can be applied at any part of the absorbent cotton fleece. Since the fleece which is somewhat constricted in the mouth-- piece resumes its original width after emerging therefrom, the loop, which was applied in a definite and constant dimension around the reduced mouthpiece, is now taut on the fleece and can, without slipping, be transported therewith to the next processing station.

It is now intended hereinafter to describe the apparatus in detail. According to FIG. 3, a gear shiftis driven in suitable manner through a chain sprocket l and has mounted on it a gearwheel 2 whichmeshes with a gearwheel 3 of an intermediate shaft. Keyed to the intermediate shaft is a further pinion 4 which meshes with a further gearwheel 5 which is rigidly connected to the clamping sleeve 13. Disposed in the clamping sleeve for longitudinal displacement, though being coupled to the clamp ing sleeve in the directionof rotation, are two hammers 14, 14a, of which the rearward guide pieces 15, a follow the control cam 17 through wheels 1. under the action of thrust springs 18.

Also mounted on the gear shaft is a pinion 5 which acts through an intermediate pinion 7 on a further pinion 8 of a chain gearwheel 9. 1 v

On the lefthand side in FIG. 3 is a chain guide 10 which guides an endless double chain 11 which'can be driven through the chain gearwheel 9. On two chain link axes is located the thread-puller 12. Also on the intermediate shaft is a control cam 19 which o-operates with a control wheel 20 on one end of a double lever, of which the other end 32 hasan adjustable stop 21 which acts on a control rod 22 of the pusher 23 which is held in its inoperative position by a thrust spring, the pusher 23 acting on the mouthpiece of the inlet passage 24 of the receiver device for the loop of a withdrawal tape 40.

Also mounted on the intermediate shaft is a disc 26 having an eccentrically disposed stud 26a on-its end disc 26 and of the pin 28a in conjunction with the spacing of the bores in the coupling piece 27, a thread guide lever 29 mounted on the pin-member 28 can be caused to pivot upwards and'downwards upon rotation of the intermediate shaft. Another construction of the drive for the three-armed thread guide leverwould be possible with a control cam, whereby, instead of the eccentric disc withstud, a cam plate with axially incorporated cam path is provided. This cam path is engaged by a wheel on the eccentrically located pin-member of the three-armed lever and, by reason of the appropriate construction of the cam path, causes the lever to pivot as desired. v v

On the inside face of the long lever am of the thread guide lever 29 which is directed towards the mouthpiece 25 is the thread guide 30. According to FIG. 2, the thread guide lever is of three-armed construction, two lever arms 29a, 29b whichare substantially shorter than the long lever arm forming with this latter an angle of in each case more than brake clamps 31a, 31b being provided at each end of the shorter arms.

Reference numeral 33 denotes a gear casing in which a guide sleeve 33a for the clamping sleeve 13 is secured and on which the chain gearwheel -9 is .rotatably mounted.

In FIG. 2, reference numerals 34', 34a identify angular cutters which are mounted on the hammers 14, 14a.

Reference numerals 35, 35a denote fixed control cams which act on a control device of the threadpuller, to be described in greater detail hereinafter.

The absorbent cotton fleece 36, is located inside the inlet passage v 24, the cross-section of which corresponds to thenominal width of the absorbent cotton fleece, while the cross-section of the mouthpiece 25 is in contrast of smaller width and height. Since, after emerging from the mouthpiece, the absorbent cotton fleece tends to expand again this contributes to ensuring that the loop of the withdrawal tape which is pushed off from the mouthpiece onto the absorbent cotton fleece by the pusher 23-fits snugly around the fleece.

In the right-hand bottom part of FIG. 2 is a reversing pulley 43 for the withdrawal tape 40 which is guided by the reversing pulley to the clamping and cutting device A constituted by the hammers 14, 140.

On the outside of the thread-puller 12 is the entraining means 44 which widens conically outwardly and has at its base an annular shoulder 44b which is braced on the thread-puller. The entraining means is a component part of a sleeve 440 which extends as far as the back of the thread-puller and in which the hook pin 45 is axially .the rear end of the sleeve 44c, the pin so co-operating with the control cam 35 in FIG. 2 that the hook part of the pin is pushed out beyond the end face. of the entraining means 44, into the position shown by dashdotted lines in FIG. 8. The hook pin assumes this position when the thread-puller is in the position shown in FIG. 4e. Already in FIG. 4f, the hook pin has retracted back into the entraining means, drawing the withdrawal tape, which it has now gripped, with it into the entraining means. The withdrawal tape extends laterally through the grooves 44a of the entraining means, which are so dimensioned that the doubled withdrawal tape, even in the angled state, can pass with a certain restriction through the grooves and the hook.

The guide groove at 149, formed by the conically widening entraining means serves to guide the closed end or the loop of the gripped withdrawal tape. This loop is thrown off by the ejector mushroom 47 which engages in a cut-out in the annular shoulder 44b and the entraining means 44 at 44f and, in the inoperative position shown in FIGS. 6, 7 and 9, engages under the loop located in the guide groove 49. The shank of the ejector mushroom 47 is screwed into a sleeve 51, on the annular shoulder 51a of which there is braced a thrust spring 52, the other end of which bears on an inner shoulder of the thread-puller housing. The annular shoulder 51a is guided in the thread-puller housing; an outwardly-projecting stud 53 on the ejector mushroom 47 so co-operates with the control can 35a that, in a midway position of the thread-puller, between the positions shown in FIGS. 4f and 4g, the mushroom ejects the loop laid around the entraining means 44. The extreme ejection position of the ejector mushroom 47 is shown in FIG. 10, while FIG. 9 shows the thread gripping position of the hook 45, in other words its extended position, when the hook is open in the direction of movement of the threadpuller.

By virtue of this eccentric location of the plateshaped ejector mushroom in relation to the entraining means, the loop located on the entraining means is lifted on one side, Le, a part of the thread extending in a straight line first leaves the upper edge of the entraining means, after which the loop sliding along the outermost edge of the entraining means is lifted off gradually and not abruptly.

In FIGS. 11 to 14, the thread guide 30 mounted on the end of the long arm of the three-armed thread guide lever 29 is shown on an enlarged scale and in greater detail. It consists of a conically tapering thread guide pin 30a, which merges into a thread guide nose 30b extending obliquely downwardly beyond the periphery of the pin-member and constructed fairly flat and substantially rectangularly in elevation. Screwed to the pin-member, there is a thread-guide hook 30c on the back of the lever 29 which, on the underside of the lever, at an acute angle in relation to the pin axis (see FIG.'14), is guided forwards towards the side which faces the pivot axis of the thread guide lever 29, being, in the region of the conical foot of the thread guide pin 30a, guided obliquely upwardly to approximately halfway up the thread guide nose, slightly overlapping this in side elevation, as shown in FIG. 13, so that between the thread guide nose 30b and the thread guide hook 30c a gap 30d (FIG. I l) and a thread guide chamber 30e (FIG. 3) are left free. The cross-section of the thread guide chamber 30e according to FIG. 13 is so dimensioned that the doubled withdrawal tape can, in the elongated state, be pulled without any great restriction through the thread guide chamber. The thread guide 30, according to FIGS. 4b, 4c and 4d, receives the two strands of thread of the withdrawal tape, pulled by the thread-puller, and carries them out of the thread plane 41 into the farther forwardly or outwardly located thread plane 42. At the same time, the length of thread released is compensated. The thread is transferred by the oblique shape of the thread guide nose, the thread guide hook 30c preventing the doubled withdrawal tape from slipping off the thread guide pin or out of the chamber 30e.

The brake clamps 31a, 31b of the three-armed thread guide lever 29 are shown in greater detail in one embodiment which is shown on an enlarged scale in FIGS. 15 to 17. According to these drawings, the brake clamps on the two short lever arms of the thread guide lever each consist of a pin-member 41c widened at its outer end into a plate 31d. On the rear face which is towards the lever arm 29a, 2912, the plate is provided with a thread guide chamber 3le which extends in such a way that the withdrawal tape 40, according to the differing angle positions which arise during gripping, finds a free space, the cross-section of which is smaller than that of the doubled withdrawal tape. On the back of the plate 31d, there is a plate disc 31f which is displaceable on the pin-member 31c and which is subject to the pressure of a spring 31g which encloses around the pinmember 31c, its other end being braced on the lever arm 29a, 29b of the thread guide lever 29. The plate 31d and the plate disc 31f are chamfered on their periphery to form a V-shaped peripheral groove 31h into which the doubled withdrawal tape engages and so can engage more easily into the thread guide member Me.

The clamping and cutting device A can be seen in greater detail and on an enlarged scale in FIGS- 18 to 22. The two hammers 14, 14a co-operate with the end face 13a of the clamping sleeve 13 in order to grip the thread. Each of the two hammers 14, 14a is equipped with an angular cutter .34, 340 which is maintained springingly against the hammer by a screwed bolt 50 through locknuts 54, a washer 55 and plate springs 56. On the opposite side, the screwed bolt at the same time retains a matching cutter 39, 39a in a corresponding recess in thehammer. The two angular cuttersare furthermore secured against pivoting by means of a guide pin 340. The L-shaped arm of the angled cutters forms an acute angle with the corresponding matching cutter 39a, 39 against which it is pressed by the plate spring that when the hammer 14a carrying the angled cutter is lifted from the end face of the clamping sleeve 13,

the cutting process takes place as can be seen from the final position of the cutting process shown in FIG. 21. In this way, the front clamped end of the completed loop is released. The end of the withdrawal tape which leads to the supply spool is held fast for initiation of a new looping process between the hammer l4 and the sleeve 13 (FIG. 4d). FIG. 22 shows the released position of the hammer 14 in which the withdrawal tape can be pulled without hindrance into the gap between the clamping sleeve 13 and the hammer, until the desired loop length is attained. By virtue of providing two cutters and two hammers, the rotary speed of the clamping and cutting device is so selected that when a loop is formed, the clamping and cutting device performs only half a revolution. In consequence, each cutter cuts at only every second loop formation. This guarantees an extremely high operational reliability in the entire control process for loop formation and loopingthrough.

I claim:

1. A method of looping a double-thickness withdrawal tape around an absorbent cotton fleece used particularly for the manufacture of tampons for feminine hygiene, for looping the open ends through the closed end and for drawing the withdrawal tape taut until the absorbent cotton fleece is closely encircled by the loop formed, the path of rotation of a continuously rotating thread-puller encircling the absorbent cotton fleece as well as a withdrawal tape receiver device for guiding the fleece axially and transversely to the plane of rotation of the thread-puller, and a loop ejector de- 'vice, the thread-puller being provided with a control device which is adjustable by control cams against the action of restoring springs, which comprises gripping the withdrawaltape behind its leading end and clamping the same fast in a clamping and cutting device partially disposing said tape arounda receiver device so that in the region of the dead-centre position of the thread-puller opposite the clamping and cutting device, gripping the doubled withdrawal tape by a thread guide and moving the same in the plane of rotation of the thread-puller cutting the tapewhile releasing the same at the same time clamping fast the following end of the withdrawal tape diverting the length of withdrawal tape from the receiver device to the hread' guide into a second outer plane. into a second outer-plane, gripping such diverted withdrawal tape by a hook and pushing said hook from the entraining means of the threadpuller while ejecting a loop from an ejector mushroom out of a thread-puller and passing it around the entraining means over the two ends of the withdrawal tape while the same are gripped by the hook, whereby forming a loop, drawing the loop tight gradually releasing the ends of the withdrawal tape and thereafter pushing the loop formed off onto the absorbent cotton fleece.

2.. In an apparatus for looping a double-thickness withdrawal tape around an absorbent cotton fleece used particularly for the manufacture of tampons for feminine hygiene, for looping the open end through the closed end and for drawing the withdrawal tape taut until the absorbent cotton fleece is closely encircled by the loop formed having an endless flexible member movable continuously in a vertical plane, on which a thread-puller is attached, said endless flexible member enclosing a withdrawal tape receiver device adaptable to axially guide the absorbent cotton fleece transversely to the plane of rotation of the thread-puller, and a loop ejector device, the thread puller being provided witha control device which is adjustable by control cams against the action of restoring springs, the improvement which comprises a clamping and cutting device comprising two hammers, which, under cam control, are axially adjustable inside of a rotatable clamping sleeve to clamp a thread alternately against the end face of said sleeve and are coupled in the direction of rotation to a clamping sleeve coaxial with the axis of a reversing wheel for said endless flexible carrier member for the thread-puller, and are in each case equipped with co-operating cutters, said apparatus having inside the cylindrical entraining means means adapted to project from the thread puller and widen conically outwards forming a guide groove for a withdrawal tape, a cam-operated hook-pin held by a front spring in an inoperative position and cooperatively associated with a control cam, a cam-operated ejector mushroom associated with and located parallel to and at a distance from the hook pin, a thread guide leaver adapted to pivot upwards and downwards in a vertical plane of r0-. tation of said thread-puller the pivot point of said thread guide puller being located between a withdrawal tape receiver device and the clamping and cutting device at the height and in the vicinity of the ladder, the free end of the long lever arm of the thread guide lever being directed away from the clamping and cutting device and constituting a thread guide, a brake clamp secured on each of the two ends of two further substantially shorter lever arms of the thread guide lever, the receiver device for the withdrawal tape comprising an inlet passage for the fleece strip.

3. An apparatus according to claim 2 wherein said apparatus has a thread guide pin having an obliquely downwardly directed nose extending beyond its periphery, a thread guide hook extending on the underside thereof at an acute angle to the axis of the pin-member towards the side which faces the centre of gravity of the three-armed thread guide lever, its front end being bent upwards to approximately the longitudinal centre of the thread guide nose to form a free gap and a thread guide chamber.

4. An apparatus according to claim 2 wherein the apparatus further comprises two shorter lever arms on said thread guide lever which are directed in each case upwards and downwards symetricallywith respect to a long lever arm of said thread guide puller, each forming therewith an angle of over an upper brake clamp adaptable to engage beneath withdrawal tape before said tape is gripped by a thread guide and while a lower brake clam, which is adaptable to engage beneath the end of a withdrawal tape engages the same before a thread-puller has reached its starting point.

5. An apparatus according to claim 2 wherein the apparatus comprises an upper brake clamp and a lower brake clamp one on each short lever on of a thread guide lever, each comprisinga pin-member which at its outer end is widened into a plate which has, on its rear side which is towards the lever arm, a thread guide chamber which extends so that a withdrawaltape, according to the different angular positions during gripping, finds a free space and across section ,of which is smaller than that of the double withdrawal tape, a plate disc displaceable on the pin-member bearing on the back of the plate under the thrust of a spring which adaptable to engage around the pin-member, itsother end being braced on the lever arm of the thread guide lever.

6. An apparatus according to claim 2,wherein .a disc is mounted on an intermediate shaft having an eccentric stud projecting from its end face and engaging into a bore in a coupling piece, into another bore which engges a pin-member located eccentrically on the axis of a three-armed thread guide lever, whereby upon a rotation of the intermediate shaft, the three-armed thread guide lever can be caused by the pin-member'to perform an upwardly and downwardly directed pivoting movement.

7. An apparatus according to claim 2 wherein in an apparatus further comprises angled cutters associated with each hammer, and with a countercutter mounted on'said hammer at an acute angle, therefrom each of which is held on by means of a spring againstthe cutting surface of the other cutter on the other hammer,

being maintained non-rotatable by means of a guide pm.

8. An apparatus according to claim 2 wherein there is a cylindrical entraining means projecting from the thread-puller which is widened conically outwardly, forming a guide groove for a withdrawal tape, the outside of the hook-pin which is mounted in the entraining means and held in an inoperative position by means of a thrust spring being approximately flush with the outside face of the entraining means, while the rearward end of the stud in the hook-pin co-operates with a control cam.

9. An apparatus according to claim 8 wherein said association comprises two small grooves in the entraining means flanking the hook on both sides, the grooves extending from both sides into the free cross-section of the hook of said hook-pin, which is directed in the direction of rotation of the thread-puller.

10. An apparatus according to claim 2 wherein the plate-shaped ejector mushroom engages into a cut-out which, breaking through the guide groove for the withdrawal tape, extends into the entraining means, to a location close to the hook-pin, the outer face of the mushroom, when this latter in its inoperative position,

being approximately in the plane formed by the base line of the guide groove.

11. An apparatus according to claim 10, wherein the mushroom is screwed into a guide sleeve, on a rear annular shoulder of which is braced one end of a thrust spring, the other end of which bears on an inner annular shoulder in the thread-puller, a stud at the rear of the guide sleeve co-operating with a fixed .control cam.

on a fixed mouthpiece slightly beyond said mouthpiece. 

1. A method of looping a double-thickness withdrawal tape around an absorbent cotton fleece used particularly for the manufacture of tampons for feminine hygiene, for looping the open ends through the closed end and for drawing the withdrawal tape taut until the absorbent cotton fleece is closely encircled by the loop formed, the path of rotation of a continuously rotating thread-puller encircling the absorbent cotton fleece as well as a withdrawal tape receiver dEvice for guiding the fleece axially and transversely to the plane of rotation of the thread-puller, and a loop ejector device, the thread-puller being provided with a control device which is adjustable by control cams against the action of restoring springs, which comprises gripping the withdrawal tape behind its leading end and clamping the same fast in a clamping and cutting device partially disposing said tape around a receiver device so that in the region of the dead-centre position of the thread-puller opposite the clamping and cutting device, gripping the doubled withdrawal tape by a thread guide and moving the same in the plane of rotation of the thread-puller cutting the tape while releasing the same at the same time clamping fast the following end of the withdrawal tape diverting the length of withdrawal tape from the receiver device to the hread guide into a second outer plane, into a second outer plane, gripping such diverted withdrawal tape by a hook and pushing said hook from the entraining means of the thread-puller while ejecting a loop from an ejector mushroom out of a thread-puller and passing it around the entraining means over the two ends of the withdrawal tape while the same are gripped by the hook, whereby forming a loop, drawing the loop tight gradually releasing the ends of the withdrawal tape and thereafter pushing the loop formed off onto the absorbent cotton fleece.
 2. In an apparatus for looping a double-thickness withdrawal tape around an absorbent cotton fleece used particularly for the manufacture of tampons for feminine hygiene, for looping the open end through the closed end and for drawing the withdrawal tape taut until the absorbent cotton fleece is closely encircled by the loop formed having an endless flexible member movable continuously in a vertical plane, on which a thread-puller is attached, said endless flexible member enclosing a withdrawal tape receiver device adaptable to axially guide the absorbent cotton fleece transversely to the plane of rotation of the thread-puller, and a loop ejector device, the thread puller being provided with a control device which is adjustable by control cams against the action of restoring springs, the improvement which comprises a clamping and cutting device comprising two hammers, which, under cam control, are axially adjustable inside of a rotatable clamping sleeve to clamp a thread alternately against the end face of said sleeve and are coupled in the direction of rotation to a clamping sleeve coaxial with the axis of a reversing wheel for said endless flexible carrier member for the thread-puller, and are in each case equipped with co-operating cutters, said apparatus having inside the cylindrical entraining means means adapted to project from the thread puller and widen conically outwards forming a guide groove for a withdrawal tape, a cam-operated hook-pin held by a front spring in an inoperative position and cooperatively associated with a control cam, a cam-operated ejector mushroom associated with and located parallel to and at a distance from the hook pin, a thread guide leaver adapted to pivot upwards and downwards in a vertical plane of rotation of said thread-puller the pivot point of said thread guide puller being located between a withdrawal tape receiver device and the clamping and cutting device at the height and in the vicinity of the ladder, the free end of the long lever arm of the thread guide lever being directed away from the clamping and cutting device and constituting a thread guide, a brake clamp secured on each of the two ends of two further substantially shorter lever arms of the thread guide lever, the receiver device for the withdrawal tape comprising an inlet passage for the fleece strip.
 3. An apparatus according to claim 2 wherein said apparatus has a thread guide pin having an obliquely downwardly directed nose extending beyond its periphery, a thread guide hook extending on the underside thereof at an acute angle to the axis of the pin-member toWards the side which faces the centre of gravity of the three-armed thread guide lever, its front end being bent upwards to approximately the longitudinal centre of the thread guide nose to form a free gap and a thread guide chamber.
 4. An apparatus according to claim 2 wherein the apparatus further comprises two shorter lever arms on said thread guide lever which are directed in each case upwards and downwards symetrically with respect to a long lever arm of said thread guide puller, each forming therewith an angle of over 90*, an upper brake clamp adaptable to engage beneath withdrawal tape before said tape is gripped by a thread guide and while a lower brake clam, which is adaptable to engage beneath the end of a withdrawal tape engages the same before a thread-puller has reached its starting point.
 5. An apparatus according to claim 2 wherein the apparatus comprises an upper brake clamp and a lower brake clamp one on each short lever on of a thread guide lever, each comprising a pin-member which at its outer end is widened into a plate which has, on its rear side which is towards the lever arm, a thread guide chamber which extends so that a withdrawal tape, according to the different angular positions during gripping, finds a free space and a cross section of which is smaller than that of the double withdrawal tape, a plate disc displaceable on the pin-member bearing on the back of the plate under the thrust of a spring which adaptable to engage around the pin-member, its other end being braced on the lever arm of the thread guide lever.
 6. An apparatus according to claim 2 wherein a disc is mounted on an intermediate shaft having an eccentric stud projecting from its end face and engaging into a bore in a coupling piece, into another bore which engges a pin-member located eccentrically on the axis of a three-armed thread guide lever, whereby upon a rotation of the intermediate shaft, the three-armed thread guide lever can be caused by the pin-member to perform an upwardly and downwardly directed pivoting movement.
 7. An apparatus according to claim 2 wherein in an apparatus further comprises angled cutters associated with each hammer, and with a countercutter mounted on said hammer at an acute angle, therefrom each of which is held on by means of a spring against the cutting surface of the other cutter on the other hammer, being maintained non-rotatable by means of a guide pin.
 8. An apparatus according to claim 2 wherein there is a cylindrical entraining means projecting from the thread-puller which is widened conically outwardly, forming a guide groove for a withdrawal tape, the outside of the hook-pin which is mounted in the entraining means and held in an inoperative position by means of a thrust spring being approximately flush with the outside face of the entraining means, while the rearward end of the stud in the hook-pin co-operates with a control cam.
 9. An apparatus according to claim 8 wherein said association comprises two small grooves in the entraining means flanking the hook on both sides, the grooves extending from both sides into the free cross-section of the hook of said hook-pin, which is directed in the direction of rotation of the thread-puller.
 10. An apparatus according to claim 2 wherein the plate-shaped ejector mushroom engages into a cut-out which, breaking through the guide groove for the withdrawal tape, extends into the entraining means, to a location close to the hook-pin, the outer face of the mushroom, when this latter in its inoperative position, being approximately in the plane formed by the base line of the guide groove.
 11. An apparatus according to claim 10, wherein the mushroom is screwed into a guide sleeve, on a rear annular shoulder of which is braced one end of a thrust spring, the other end of which bears on an inner annular shoulder in the thread-puller, a stud at the rear of the guide sleeve co-operating with a fixed control cam.
 12. An apparatus according to claim 2, wherein the houSing of the thread-puller is a constituent part of said endless flexible member.
 13. An apparatus according to claim 2 wherein the inlet psssage in the receiver device corresponds in cross-section to the nominal width of the fleece, the mouthpiece of the inlet passage consisting of a thin-walled steel nozzle, through which the fleece can be pulled said nozzle having a smaller width than the inlet passage.
 14. An apparatus according to claim 2, wherein an annular pusher is provided which is axially displaceable on a fixed mouthpiece slightly beyond said mouthpiece. 